How do you make Windows Defender Firewall rule for MS Teams to work?

Question

I'm currently configuring Windows Defender on Windows 10 setting up such that only restricted apps can be run.

In one of the allowed apps, I want to have Microsoft Teams be able to run under this environment.

I added the following exe files as allowed programs under "send rules".

• AppData\\Local\\Microsoft\\Teams\\current\\Teams.exe
• AppData\\Local\\Microsoft\\Teams\\Update.exe

but so far no luck.

If anyone could guide me on how to configure it correctly, much appreciated.

Answer 1

You cannot refer directly to %appdata% generically across all users. A firewall rule needs to be created per instance of Teams ie per user.

You can use the Microsoft suggested sample PowerShell script to set up a firewall rule per existing user on a workstation. Available here: https://docs.microsoft.com/en-us/microsoftteams/get-clients#sample-powershell-script---inbound-firewall-rule

This doesn't help for the next user who logs into the workstation when there is no firewall rule preemptively created for them.

You will have to create a scheduled task to create a firewall rule ( or check for whether one exists already) on user logon.